This is a research study of patients with menopausal symptoms such as hot flashes, night sweats and mood disturbances. Currently physicians prescribe hormones in the form of pills or patches to women for the relief of these symptoms. While there are benefits of hormones in addition to relief of hot flashes such as protection from osteoporosis and possible protection from heart disease, there are also potential risks of hormone replacement therapy, including the possible increased risk of breast or uterine cancer. Currently, all of the hormones prescribed by physicians are derived from animal sources. There is some evidence that increasing dietary intake of some vegetables, such as soybeans, which contain plant estrogens, may prove beneficial in treating women with menopausal complaints and preserving the benefits of traditional hormone replacement therapy while avoiding the risks of hormone replacement therapy. However, very few studies have investigated the effectiveness of soy supplementation. The purpose of this study is to therefore determine whether soybean protein supplementation is as effective as hormones currently being prescribed by physicians in relieving menopausal complaints and reducing heart disease risk.